Marking machine



Oct. 30, 1928. 1,689,349 E. L. LANG ET AL MARKING MACHINE Original Filed 001;. 9, 1922 2 Sheets-Sheet 1 lnvenTor-s.

' 5 \4 Elmer L..l c1ng George H. Lang Oct. 30, 1928. 1,689,349

E. L. LANG ET AL MARKING MACHINE Original Filed Oct. 9, 1922 2 sh et -$heet 2 Fig. 2.

lnvenTers.

Elmer L Long George H.Lqng

by MEM Afiys.

Patented Oct. 30, 1928.

UNITED STATES" PATENT OFFICE.

ELMEB L. LANG AND GEORGE r. ANG, or BosToN, MASSACHUSETTS.

MARKING MACHINE.

Original application filed October 9, 1922 Serial No. 593,416. Divided and this January 15, 1927.

This application is a division of our application Serial No. 5593, 116, filed October 9, 1922, now Patent No. 1,615,017.

This invention relates to marking machines of the type comprising a platen or work support and a printinghead movable toward and from the platen to make the printed impression.

The principal feature of the invention relates to novel means for supporting the platen. According to this feature the platen.

is yieldingly supported by a spring and is at all times free to be moved downward against the action of the spring, a locking device being provided which normally prevent-s the platen from movingupwardly but which is rendered inoperative during the making of the printed impression. In the drawings wherein we have'illustrated a selected embodiment of the invention Fig. 1 is a side View of a marking machine embodying our invention Fig. 2 is a partial front view. The marking machin'eherein shown is of that general type comprising a stand or frame 1 having a head 2 in which' reciprocates a vertically-moving plunger 3 carrying a printing head 4 which is movable toward and from a. work support or platen 5 on which the'work to be marked is supported.

The printing head may carry adjustable type disks having printing characters 6 thereon and these are shown as being inked that it will move downwardly when pressure is applied thereto. A locking device is provided for the platen which will at all times permit itto'be moved downwardly freely but which willlock it from, upward movement except during thetime that the printed impression is being made. The platen is carried by a plunger 10 which is slidable through a guiding opening 11 formed in a supporting bracket 12. The lower end of theplunger is pivotally connected at 13- to a lever 1.4, which is pivoted intermediate its ends to the frame as shown at 15, the end of the lever I being acted upon by a pulling spring 16 which tends normally to raise the plunger and thus the platen, Any downward movement of the I application filed Serial No. 161,317.

platen, therefore, in opposition to the action of the spring 16.

As stated above a locking device is provided which prevents the platen from, moving upwardly except at the time that the printed impression is made but which permits it at all times to be moved downwardly freely. This locking device might be called a oneway locking device because it functions tQlQSlZI'ZLlIl-111OVO1H611tof the platen in one direction only, the platen being at all times free to be moved downwardly but being re.

that is sli d ably mounted in a lateral extension 19 of the bracket 12, said pawl being guided by means of a pin 20 extending laterally from the pawl and which operates in a slot 21 formed in the extension 19; The pawl is shown as acted upon by springs 22 which urge it forwardly into engagement with the ratchet 17.

The pawl and ratchet are constructed, as will be seen from Fig. 2, so that. the platen can be moved freely downwardly and during such downward movement the pawl merely clicks over the teeth of the ratchet. The pawl,

. however, will normally lock the ratchet and consequently the platen from upward movement. v

Means are provided, however, whereby this locking pawl is released from. the ratchet during the time that the printing impression is being made and so that at such time the.

platen may be moved upwardly by the action of the spring to bringth-e work into'engage ment with the printing head. Forthis purpose a rock shaft'23 1s shown which is our-.

nalled in suitable bearings 24 carried by the frame and which has at one end an upstanding arm 25 that is adapted to engage the pin 20 of the pawl. When the shaft isrocked anti-clockwise Fig; 2 the upstanding arm 25 will engage the pin 20 and thus withdraw the pawl 18 fromlocking engagement with, the Y ratchet. This frees the platen so that it may be moved upwardly by the spring 16.

Means are provided whereby this releasing of the locking pawlis accomplished only at the time that the printing head is'in its lowered or printingzposition and hence when each printed impression is being made the l platen is released and is thus move upw ly by the spring as far as permitted by the print- 1 ng head.

The rock shaft is shown as having another arm 27 fast theretoto which is pivotally connected a link 28. This link is depressed periodically and at the time the printing impression is being made by means of a cam .29 which is fast on a shaft 30 that rotates in timed relation with the movement of the head el, said cam engaging a cam roll 31 which is carried by a link. The upper end of the link shown as having aslot'32 therethrough through which the shaft extends this slot thus serving to guide the upper end of the link and hold it trom'lateral movement. The roll 31 is maintained in engagement with the cam 99 by means of a pulling spring which is connected one end to the link and at the other end to. the frame 1. The cam 9-9 makes one rotation for each complete excursion of the printing head 1 and it is so timed and arranged that the high point thereof is in engagement with the roll 31 at the time that the printing head is in its lowered position.

It will be observed that the engagement oi the high point 01 the cam with the roll 31 will depress the link E28 and thereby rock the shaft to withdraw the pawl 18 from its locking engagement with the ratchet thus unlocking the platen and such unlocking occurs just as;

the printing head reaches its lowered or printing position.

In using the device it is possible to place a stack or pile of pieces to be marked on the platen which may be depressed into its lowered position before the machine is started if desired, or may be left in elevated position. If the platen has been depressed then when the machine is started and the printing head is brought into its lowered position the lock will be released and the spring 16 will force the platen upwardly until the upper piece of the stack meets'the typecharacters on the printing head thus causing a printed impression to be made. As the printing head moves upwardly after making the printed impression the latch 18 will automatically engage the ratchet and thus lock the platen in its lowered position. The operator willthen remove the marks-cl articleleaving an unmarked article on the top of the pile and duringlhe next printing operation the platen will be again unlocked so as to ensure a. proper ei'igagen'ient oi the top article of the stack with the printing characters of the printing'head.

it on the other hand, the platen left in its cit-rated position when the pile or stack of pieces to be marked is placed thereon then t marking head during its first downward.

movement will engage the top piece of the stack and will force the platen downwardly to a position determined by the lowest point to which lh marking head is carried, the top. piece of the pile being marked during this dowmvard movement. This downward movement of the platen is treely permitted because of the character of the locking device but as soon the printing head starts to move upwardly the lock will function to retain the printing head in its lowered position.

\Ve claim:

In a marking macl with a yieldiiiglvslippor the work, of a oneovav lock for the platen which permi s the platen at all times to be depressed to the full extent of its downward movement but wnich normally restrains the platen from upward movement, a printing head movable toward and from the platen, and means to render the lock inoperative during the making of the printed impression.

2. In a marking machine the combination with a spring-sustained platen to support the work, said platen being at all times to be depressed against the action of the spring to ride the combination the lowest limitof its movement, of a pawl and ratchet device to restrain the platen from upward movement a prmting head movable toward and from the platen; and means to render the pawl and ratchet deviceinoperati o while the printing head makingcthe pr. cited impression, i

3. In a marking machine, the combination with a spring-supported platen. to receive the work of a ratchet with the platen,

a spring-pressed pawl engaging the ratchet and co -operating therewith to prevent upward movement of the platen, said platen being "free at all times to be moved downwardly against the action of the spring to the lower limit of its movement printing head moV-i able toward and from the platen, and means to release the pawl from operative engage ment with the ratchet when the printing head is in its printing position.

4. In a marking machine the combination with a vertic llysmovable printin head, of a spring-supported platen to recei he work, a ratchet rigid with the platen a swing-pressed pawl co-opcrating with the ratchet to restrain the platen from upward movement, said ed platen to receive 

